<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        input[type="text"] {
            border: 1px solid red;
        }
        
        div :nth-child(odd) {
            color: red;
        }
        
        div {
            width: 200px;
            height: 30px;
            border: 1px solid red;
        }
        
        div::after {
            content: "我";
        }
    </style>
</head>

<body>
    <input type="text">
    <input type="text">
    <input type="text">
    <input type="text">
    <input type="text">
    <input type="search" name="" id="">
    <input type="search" name="" id="">
    <input type="search" name="" id="">

    <button>按钮</button>
    <button>按钮</button>
    <button>按钮</button>
    <button>按钮</button>
    <button>按钮</button>
    <button>按钮</button>
    <button>按钮</button>
    <div>是</div>

</body>

</html>